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91.
NO在外源性自由基损伤内皮细胞中的作用 总被引:1,自引:0,他引:1
目的:探讨NO在外源性自由基损伤内皮细胞(EC)中的作用。方法:培养的家兔主动脉EC随机分为四组:1.对照组(C,n=6):2mlPBS;2.自由基损伤组(X/XO,n=6):2mlPBS中加入终浓度为1μmol/mlX,0.1IU/ml的XO;3.L-Arg组:含终浓度为10^-3M的L-Arg,余同2;4.SNP组:含终浓度为10^-5M的SNP,余同2。在观察L-NAME对自由基损伤的作用时 相似文献
92.
M I Colado E O'Shea R Granados A Misra T K Murray A R Green 《British journal of pharmacology》1997,121(4):827-833
- It is well established that 3,4-methylenedioxymethamphetamine (MDMA or ‘ecstasy'') is neurotoxic and produces long term degeneration of cerebral 5-hydroxytryptamine (5-HT) nerve terminals in many species. Since MDMA is used extensively as a recreational drug by young people, it is being ingested by many women of child bearing age. We have therefore examined the effect of administering high doses of MDMA to rats during pregnancy on the cerebral content of both the dams and the neonates.
- MDMA (20 mg kg−1, s.c.) was injected twice daily on days 14–17 of the gestation period. The initial dose produced a marked hyperthermic response in the dam which was progressively attenuated in both peak height and area under the curve following further doses of the drug. The body weight of the dams decreased during the period of treatment.
- There was a modest decrease in litter size (−20%) of the MDMA-treated dams.
- The concentration of 5-HT and its metabolite 5-HIAA was decreased by over 65% in the hippocampus and striatum and 40% in the cortex of the dams 1 week after parturition. In contrast, the content of 5-HT and 5-HIAA in the dorsal telencephalon of the pups of the MDMA-treated dams was the same as that seen in tissue from pups born to control animals.
- Administration of MDMA (40 mg kg−1, s.c.) to adult rats increased thiobarbituric acid reacting substances (TBARS) in cortical tissue 3 h and 6 h later, indicating increased lipid peroxidation. No increase in TBARS was seen in the cortical tissue of 7–10 day neonates injected with this dose of MDMA 3 h or 6 h earlier.
- The data suggest that exposure to MDMA in utero during the maturation phase does not produce damage to 5-HT nerve terminals in the foetal rat brain, in contrast to the damage seen in the brains of the mothers. This may be due to MDMA being metabolized to free radical producing entities in the adult brain but not in the immature brain or, alternatively, to more effective or more active free radical scavenging mechanisms being present in the immature brain.
93.
NEUMANN F. J.; OTT I.; WILHELM A.; KATUS H.; TILLMANNS H.; SCHoMIG A. 《European heart journal》1994,15(2):171-178
The study investigated inflamatory responses in evolving myocardialinfarction. Fifteen patients with acute myocardial infarction,who had undergone balloon recanalization of the infarct-relatedcoronary artery within 4 h after onset of symptoms, were examined.Blood samples were obtained through the guiding catheter andfrom the pulmonary artery before and immediately after successfulrecanalization. After recanalization, plas from the pulmonaryartery was 47% (quartiles: l9%, 78; P =0·001) more chemotacticto neutrophils from normal donors than before recanalization.Furthermore, significant changes in neutrophil function werefound in the pulmonary artery. Compared to the values beforerecanalization, the nitroblue tetrazolium score rose by 31%(quartiles: 4%, 37% P=0·003), FMLP-stimulated superoxideanion production by 10% (quartiles: 0%, 39% P=0·020),and chemotaxis by 46% (quartiles: 0%, 81%, P=0·011),while neutrophil filterability decreased by 28% (quartiles:15%, 47%; P=0·010). No significant changes in neutrophilparameters were found in the arterial blood The study indicatesthat chemoattractants are released in the early reperfusionperiod of evolving myocardial infarction. These chemoattractantsmay act as inflammatory mediators causing neutrophil activation. 相似文献
94.
Effects of granulocyte colony-stimulating factor upon coxsackievirus B3 myocarditis in mice 总被引:1,自引:0,他引:1
HIRAOKA Y.; KISHIMOTO C.; TAKADA H.; SUZAKI N.; SHIRAKI K. 《European heart journal》1995,16(12):1900-1906
Granulocyte colony-stimulating factor is a potent activatorof mature granulocytes, and subsequently enhances superoxiderelease. The purpose of this study was to investigate the effectsof granulocyte colony-stimulating factor upon murine coxsackievirusB3 myocarditis in relation to free radical-mediated cardiacdamage. Two-week-old, male, C3H/He mice were inoculated intraperitoneallywith coxsackievirus B3. Gramulocyte colony-stimulating factor20 µg.kg1. day1, polyethylene glycol-conjugatedsuperoxide dismutase (an enzyme catalyzing the conversion ofO2- to H2O2) 1 x 103 U.kg1 day1 and granulocytecolony-stimulating factor 20 µg. kg1 day1,plus polyethylene glycol-conjugated superoxide dismutase 1 x103 U.kg1. day1, were injected subcutaneouslydaily on days 0 to 14. Treated groups were compared to the infected,untreated group. The survival rate in the polyethylene glycol-conjugatedsuperoxide dismutase group was higher than that of the untreatedgroup on day 14, but on day 7, cardiac pathology was not significantlydifferent among the four groups. On day 14, the scores of cellularinfiltration, myocardial necrosis and calc were lower in thepolyethylene glycol-conjugated superoxide disnuitase group andin the granulocyte colony-stimulating factor plus polyethyleneglycol-conjugated superoxide dismutase group than in the untreatedgroup. The myocardial virus titres on days 7 and 14 did notd sign y among the four groups. The number of total white bloodcell and neutrophil counts were signifIcantly greater in thegranulo cyte colony-stimulating factor group than in the untreatedgroup on day 7. Taken altogether with the previous reports andpresent evidence that the administration of granulocyte colony-stimulatingfactor did not exacerbate coxsackievirus B3 myocarditis, itmay be that oxygen-free radicals appeared to be derived notfrom leukocytes but from other components in this experimentalmodel of myocarditis, whereas the myocardium was inflamed withleukocytes. 相似文献
95.
本文报告以无菌剖腹产术净化小鼠肝炎病毒感染的小鼠种群的结果。剖腹产术前100%感染小鼠肝炎病毒的小鼠种群,经无菌剖腹产术净化后,结果均为阴性,并经5年的大规模生产、繁殖,至今仍保持阴性结果。 相似文献
96.
Clinical and experimental study on treatment of acute cerebral infarction with Acanthopanax Injection 下载免费PDF全文
AlotofclinicalmaterialofintegratedtraditionalChineseandwesternmedicine(TCMWM)indicatedthatthemainpathologicalchangeofcerebralischemicapoplexyis“TheblockageofCollateralsbybloodstasisresultedfromQi,whichisunabletopromoteblood”.AcanthopancisSeniticosi(R… 相似文献
97.
CHEN Zhichao ZOU Ping YOU Yong LIU Zhongping XIANG Jianping YU Dongjiao Institute of Hematology Tongji Medical University Wuhan 《华中科技大学学报(医学英德文版)》1999,19(3):190-193
Thegrowthofleukemiainsemisolidcultureinvitrowasdependentonthepres-enceofexogenousserum.Serumisamix-turecontaininglargenumberofunidentifiedchemicalcomponentsandunidentifiedbio-logicallyactivesubstances[1],whichprovidethenutrientsnecessaryforthecellgro… 相似文献
98.
99.
利用Marmarou氏脑损伤动物模型,测定大鼠脑损伤后不同时间和部位的丙二醛(MDA)含量。结果示:损伤后1h,额叶、顶叶、脑干等处的MDA水平分别比对照组高出367%,418%和351%(P<0.01),并持续增高,伤后4h达高峰后缓慢下降,伤后24h仍明显高于对照组。纹状体、颞叶等处伤后1h的MDA水平升高较上述部位稍低,而分别较对照组升高169%和133%(P<0.01),伤后4h虽仍持续升高,但不超过35%。提示在大鼠弥漫性脑损伤后短期内即有自由基生成,几乎波及脑内各个部位,但程度不一。 相似文献
100.
Mair P Hoermann C Mair J Margreiter J Puschendorf B Balogh D 《Acta anaesthesiologica Scandinavica》1999,43(4):452-457
BACKGROUND: Proteolytic enzymes and oxygen free radicals released from activated leucocytes contribute significantly to the organ dysfunction associated with cardiopulmonary bypass. Leucocyte depletion during extracorporeal circulation should reduce the release of these toxic compounds and thereby improve postbypass myocardial and pulmonary function. Recently, a leucocyte-specific arterial line filter to achieve leucocyte depletion during clinical perfusion has become commercially available. The aim of this study, therefore, was to evaluate the influence of the leucocyte depleting arterial line filter on proteolytic enzyme release, oxygen free radical release and postbypass pulmonary and myocardial function in patients undergoing bypass surgery. METHODS: Forty patients undergoing elective aortocoronary bypass surgery were included into this prospective, randomized clinical study, 20 in the leucocyte depletion (LG-6 group, leucocyte-specific arterial line filter) and 20 in the control group (AV-6 group, standard arterial line filter). White cell count, differential white cell count, plasma elastase concentration, plasma malondialdehyde concentration and C-reactive protein were determined before, twice during and immediately after cardiopulmonary bypass, at the end of surgery and 6 and 20 h thereafter. RESULTS: White cell count, differential white cell count, malondialdehyde and C-reactive protein were not significantly different between LG-6 and control patients. Plasma elastase concentrations were significantly (P < or = 0.03) higher during and immediately after extracorporeal circulation in LG-6 group patients. Need for inotropic support, arterial pO2 after extracorporeal circulation and perioperative CK MB mass and troponin I release were not different between the two groups of patients. CONCLUSION: The use of a leucocyte depleting arterial line filter is associated with an increased release of the proteolytic enzyme elastase, but does not reliably and consistently achieve effective leucocyte depletion during clinical perfusion. In contrast to previous studies, we could not demonstrate any significant difference in postbypass pulmonary or myocardial function between patients perfused with the leucocyte-specific arterial line filter and control patients. Our data do not support the routine use of a leucocyte depleting arterial line filter during clinical perfusion in patients undergoing elective aortocoronary bypass surgery. 相似文献